Microorganisms which are resistant to anti-microbial agents are becoming an increasing problem around the world. For example, methicillin-resistant strains of Staphylococcus aureus (MRSA—also referred to as “golden staph”) are now multi-resistant to antibiotics and recent isolates show increasing resistance to antibiotics such as Gentamicin, Chloramphenicol, Fusidic Acid, and Rifampicin. Only Vancomycin can currently be relied on for empirical treatment. There is considerable concern that the increasing use of Vancomycin will select Vancomycin-resistant strains of MRSA so that in the near future there may no longer be any effective antibiotic therapy against hospital staphylococci. Accordingly, investigations are underway to identify alternative anti-microbial agents, particularly broad spectrum anti-microbial agents.
Hospitals are examples of environments where MRSA acquired infections are a significant problem. These infections put the patient at risk, increase the cost of care, and reduce the number of beds available. In other environments such as dental rooms, laboratories, food preparation areas, schools and so forth, it is also important to prevent or minimise the growth of such bacteria, together with other microbial agents including fungi and viruses.
Hospitals and these other environments requiring high levels of hygiene have a range of strategies to minimise the spread of such microorganisms. Prior to entering into surgery, patients are topically treated with antiseptic solutions such as chlorhexidine or povidone iodine. Carriers of MRSA are treated with such topical antiseptics, or in severe cases, are treated with antibiotics such as Vancomycin. Vancomycin is expensive to administer, and therefore effective, less expensive orally deliverable replacements would be welcomed.
The known topical antiseptics cannot be relied upon to provide sufficient protection from such bacteria, especially as more resistant strains develop. They are also not capable of being applied in other presentation forms, such as oral tablets. Such topical antiseptics also may not be effective in preventing or inhibiting the growth of other classes of microorganisms that are present in hospitals and other such environments. Although surfaces in these environments are washed down with sterilising agents and disinfectants including bleaches containing chlorine in the form of hypochlorous acid/hypochlorite ion, these agents are quite corrosive, and other alternatives are desirable.
Accordingly, there is a need for new antimicrobial and/or antibacterial agents suitable for use in these and similar applications.
All references, including any patents or patent application, cited in this specification are hereby incorporated by reference to enable full understanding of the invention. Nevertheless, such references are not to be read as constituting an admission that any of these documents forms part of the common general knowledge in the art, in Australia or in any other country. The discussion of the references states what their authors assert, and the applicants reserve the right to challenge the accuracy and pertinency of the cited documents.